With the fast development of display technology, a touch screen panel has been gradually become popular in people's lives. Currently the touch screen panel can be divided, on basis of its construction, into an Add On Mode touch screen panel, an On Cell touch screen panel, and an In Cell touch screen panel. In the Add On Mode touch screen panel, a touch screen panel and a liquid crystal display (LCD) panel are fabricated separately and then glued together to form a LCD panel with the touch function. The Add On Mode touch screen panel has the drawbacks of high fabrication cost, low light transmittance, and a large module thickness. Since touch electrodes of the In Cell touch screen panel are embedded inside the LCD panel, the overall module thickness can be reduced and the fabricating cost can be greatly decreased, making it the favorite choice of the panel manufacturers.
Currently, in the existing In Cell touch screen panels, a finger touch position is detected by virtue of the principle of mutual capacitance or self capacitance. In the case of detection by virtue of self capacitance, a plurality of self capacitance electrodes which are arranged in the same layer and insulated from each other can be arranged in the touch screen panel. In case a human body does not touch the panel, each self capacitance electrode is subject to a capacitance of a constant value. In case the human body touches the panel, the corresponding self capacitance electrode is subject to a capacitance which is the sum of the constant value and the human body capacitance. A touch detecting chip can determine the touch position by detecting variation in capacitance value of each self capacitance electrode during a touch period. In the case of detection by virtue of self capacitance, the human body capacitance can act on all self capacitance, while the human body capacitance can only act on a projection capacitance in the case of mutual capacitance. Therefore, the touch variation amount which results from the human body's touching the panel is larger in the case of the touch screen panel in which the detection is based on mutual capacitance. Therefore, as compared with the touch screen panel based on mutual capacitance, the touch screen panel based on self capacitance can effectively improve the signal-to-noise ratio of touching detection, thus improving the accuracy in touch sensing.